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Hey guys, building a rowdy SBE LS1(24x/24x on a 110+4 cam, 320cfm 243s, fast 102, 11.5:1...) and going through my blueprinting of the bottom end and I'm at a hang up..
I had my block honed to clean up the bores, they are .002" and and a few tenths over, tops...my pistons are right on the money. Last night when I Mic'd them I thought ok maybe the skirt is worn off so they're under size till I just now dug up the spec for piston OD...nope, they're well within spec, in fact they're on the top side of the spec range.
My question on that topic is, what are guys doing about honing aside from just putting new forged pistons in. I've seen builds where oe spec replacements were used and guys had the bores honed, how then would stock replacement or even original pistons be used in this scenario?? Maybe guys are winging this?
I have 2 smart directions here and 1 reckless one..buy new forged pistons and fit to my block for acceptable piston clearance, meh..yay for forged pistons but meh, more $ spent on a 3.89" bore shortblock. Option 2, source a replacement block, I know of a brand new LS6 block and crank, as in, never assembled for $750 and stick with a truly stock SBE, the reckless option..****** send it LOL. Unless the group here knows of another option? Coatings?
Bore ID vs. Piston OD
Pistons arranged for best fit
2nd topic
My crank journals mic'd in on the very high side of production spec on OD. I sourced King std. bearings and look at this **** I get for clearance!...granted it's a few tenths over, but them dudes should be tighter unless that's on purpose. It's obvious the King bearings are thinner than factory. UNLESS, my main bores are opened up, seems unlikely. I will recheck the bearing ID as I was a bonehead and didn't let these bearings come up to temp in my 85 deg garage vs. my 72 deg house before checking them.
Crank main OD vs. Main bearing ID
Last....I know my bores are up by .002" but these Mahle rings I have gapped HIGH! I'm not that concerned with ring gap with what I've read and experienced but c'mon, are these anything to worry about. I'll probably spray it but even then, 3.900 x .005" or so for n20 is still only .019-.020 range..
Main bore #1 is money at 2.7504”. Idk what the deal is, my gauges are legit, they’re certified and I’ve measured the #1 main probably 4x and that thing is .0027”-.0029”
I suppose I need to get -.001”bearings but that’s odd when everything else is mic’ing out at nominal according to factory spec. I thought king bearings were IT for these engines! Funny enough my rods are coming in at .0015” from the King rod kit, no complaints there
I went thru 2 packages of Kings main bearings on my 408 build. They wer too damn tight. I then bought a set of Fed Mogul +.001 and were right on the money at .0025- .0027.
the King rod bearings were good tho on the the 1st package of bearings.
I ended up getting the Scoggin Dickey quick piston kit with -.001 bearings and cometic .040 gaskets, they ended up having to send King XP mains which is a good upgrade, what a value on this kit! Right around $1000 shipped, came with all bearings, gaskets, forged wiseco flat tops with file fit rings, oil pump, and a couple other odds and ends. Back to the machine shop now for a hone to fit these.
I rechecked mains with these and got
.0019
.0017
.0017
.0019
.0017
Back from the dead..
this project got mothballed. Moving, having a son, loss of interest bug bit. But then one day my son started playing around in the car in the garage, then another day and another so just like that the excitement bug bit again. The time was right. He wasn’t even a figment of my imagination when I took this apart. I last wrenched on it just to put the motor in out of necessity to move it to the new house. Well now he’s been crawling around under it with wrenches “helping” so things just happen like they’re supposed to
2 months after putting those final touches on the motor and bay build she fired up and sounds healthy. She’s got just an injector and basic cam tune, running rich before I go to the dyno for a speed density tune hence that comical 3” to 4” intake connector but it does what I need for a break in and to drive it to the tuner. My little buddy calls in the monster truck car. Happy wrenching
I couldn’t be happier for you sir. Nothing in the world is more rewarding than doing something with your kid. Getting them interested in anything that requires the use of their hands besides a smartphone or tablet these days is a huge win. Good on you sir! Enjoy the car!
Nice to see you finish it, I’m doing a similar build, I left mine stock SBE after talking to a couple local engine builders that quoted me 6k+ for a rebuild and new rods and pistons for higher comp and stronger rod bolts.
Car sounds good, I look forward to seeing it tuned and fully completed.
I couldn’t be happier for you sir. Nothing in the world is more rewarding than doing something with your kid. Getting them interested in anything that requires the use of their hands besides a smartphone or tablet these days is a huge win. Good on you sir! Enjoy the car!
Congrats all the way around. Memories is all we have at the end. These you’re making are going to be amazing when you are sitting there looking back at life. 🫡
08-31-2018, 04:27 PM
Blueprinting roadblock 
